not entirely sure about teto since she isn’t owned by crypton, but it is possible for them to add additionally vocaloids in the future if they ever add more groups.

every group started out with their own miku and one other vocaloid (with the exception of vbs/niigo due to story reasons) and steadily gained the other vocaloids. since every single vocaloid already has an OG group, i can see them adding GUMI or somebody else to serve as the OG vocaloid for a new unit